An interventional guide wire or other interventional device is often used in medical procedures that attempt to establish a pathway through a heavily stenosed or chronically occluded vessel. A chronically occluded vessel is referred to as containing a chronic total occlusion (CTO). During these procedures, the guide wire or device can only be of clinical benefit to establish vessel patency if it is advanced distally into the vessel true lumen.
At times during the process of advancing the guide wire or device through the stenosed vessel or CTO, and beyond the control of the operator, the guide wire or device may inadvertently enter into the wall of the vessel itself, i.e. the sub-intimal plane or space, or dissection plane. Once in this sub-intimal plane, it becomes difficult to navigate the guide wire or device through the sub-intimal tissue to re-gain access into the vessel true lumen at points distal to the occlusion. The layer of tissue that separates the vessel true lumen from the sub-intimal plane is typically in the range from 100 to 500 micrometers for vessels in the diameter range from 2 mm to 4 mm, and from 100 to 3000 microns, in the largest vessels of the body. The composition of the tissue may be such that no guide wire or interventional device currently on the market can re-access the true lumen.
In the drawings, the same reference numbers identify identical or substantially similar elements or acts. To easily identify the discussion of any particular element or act, the most significant digit or digits in a reference number refer to the Figure number in which that element is first introduced (e.g., element 902 is first introduced and discussed with respect to FIG. 9).
Figure numbers followed by the letters “A,” “B,” “C,” etc. indicate either (1) that two or more Figures together form a complete Figure (e.g., FIGS. 50A and 50B together form a single, complete FIG. 50), but are split between two or more Figures because of paper size restrictions, amount of viewable area within a computer screen window, etc., or (2) that two or more Figures represent alternative embodiments or methods under aspects of the invention.
Unless described otherwise below, the construction and operation of the various blocks and components shown in the figures are of conventional design. As a result, such blocks need not be described in further detail herein, because they will be understood by those skilled in the relevant art. Such further detail is omitted for brevity and so as not to obscure the detailed description of the invention. Any modifications necessary to the blocks or components in the figures can be readily made by one skilled in the relevant art based on the detailed description provided herein.
The headings provided herein are for convenience only and do not necessarily affect the scope or meaning of the claimed invention.